Featured image: An artist’s concept of NASA’s InSight lander on Mars with a cutaway of the surface below. Credit: IPGP/Nicolas Sarter.
Paper: Constraints on the shallow elastic and anelastic structure of Mars from InSight seismic data
Authors: Philippe Lognonné et al.,
Scientists are able to ‘see’ the internal structure of the Earth based on seismic waves recorded during Earthquakes. Earthquakes send seismic waves out in all directions with two main types: (1) surface waves are the major culprits of Earthquake damage as they remain on the surface; (2) faster body waves can travel down within Earth’s interior. The body waves are the fastest seismic waves, consisting of the first (primary; P-wave) and second (secondary, S-wave) waves to arrive at a location away from the epicentre of an Earthquake.
Continue reading “Marsquakes give scientists an InSight to Mars”
Featured image: Lake Malawi, as seen from space. Image courtesy of ESA/MERIS, CC-BY-SA IGO.
Paper: Preferential localized thinning of lithospheric mantle in the melt-poor Malawi Rift
Authors: E. Hopper, J. B. Gaherty, D. J. Shillington, N. J. Accardo, A. A. Nyblade, B. K. Holtzman, C. Havlin, C. A. Scholz, P. R. N. Chindandali, R. W. Ferdinand, G. D. Mulibo, G. Mbogoni
Continental rifting, where one landmass slowly breaks apart into two pieces separated by a brand new ocean basin, is a fundamental part of plate tectonics. But it presents an apparent paradox: the tectonic forces pulling on the plates are thought to be much too weak to break the strong rocks of the continents.
Continue reading “How do you break up a continent?”
Featured image: A GPS station in the Sawtooth National Forest near Ketchum, Idaho. Photo by Scott Haefner (USGS).
Paper: Months-long thousand-kilometre-scale wobbling before great subduction earthquakes
Authors: J. R. Bedford, M. Moreno, Z. Deng, O. Oncken, B. Schurr, T. John, J. C. Báez, M. Bevis
We’re always on the lookout for earthquake precursors, indicators that the Earth might be gearing up for some shaking, and geophysicists think they might have found a new one: a small but measurable back-and-forth “wobble” of the land starting several months before very big earthquakes hit.
Continue reading “Tiny wobbles foreshadow big earthquakes”
Featured image: A perspective view of the seafloor at the East Pacific Rise, 9N. Made with GeoMapApp (www.geomapapp.org, CC-BY), and GMRT topography data (Ryan et al. 2009, CC-BY).
Paper: Do sea level variations influence mid-ocean ridge magma supply? A test using crustal thickness and bathymetry data from the East Pacific Rise
Authors: B. Boulahanis, S. M. Carbotte, P. J. Huybers, M. R. Nedimovic, O. Aghaei, J. P. Canales, and C. H. Langmuir
Many of our records of past sea level come from local measurements from coastal towns logged over decades or centuries, or are estimated from ice or sediment cores spanning the last few thousand years, but new research suggests that much longer records can be found in an unlikely place: imprinted deep underground in the oceanic crust.
Continue reading “Climate records written on the seafloor”
Featured image: A fence broken by the 1906 San Francisco earthquake, by G. K. Gilbert. Public domain.
the millions of people living near the San Andreas fault zone in
California, the billion-dollar question is when the next “big one”
is going to happen.
Continue reading “How to locate oceanic earthquakes without getting your feet wet”